// 2、基于以下代码完成下面四个练习
const fp = require('lodash/fp');
// 数据
// horsepower马力，dollar_value 价格 ,in_stock库存
const cars = [{
        name: 'Ferrari FF',
        horsepower: 660,
        dollar_value: 700000,
        in_stock: true
    },
    {
        name: 'Spyker C12 Zagato',
        horsepower: 650,
        dollar_value: 648000,
        in_stock: false
    },
    {
        name: 'Jaguar XKR-S',
        horsepower: 550,
        dollar_value: 132000,
        in_stock: false
    }, {
        name: 'Audi R8',
        horsepower: 525,
        dollar_value: 114200,
        in_stock: false
    }, {
        name: 'Aston Martin One-77',
        horsepower: 750,
        dollar_value: 1850000,
        in_stock: true
    }, {
        name: 'Pagani Huayra',
        horsepower: 700,
        dollar_value: 1300000,
        in_stock: false
    }
]

// 2.1 练习一
// 答：
let isLastInStock = fp.flowRight(fp.prop('in_stock'), fp.last);

// 2.2 练习二
// 答：
let getNameOfFirstCar = fp.flowRight(fp.prop('name'), fp.first);

// 2.3 练习三
// 答：
let _average = function(xs) {
    return fp.reduce(fp.add, 0, xs) / xs.length;
}
let averageDollarValue = fp.flowRight(_average, fp.map(car => car.dollar_value));

// 2.4 练习四
// 答：
let _underscore = fp.replace(/\W+/g, '_');
let sanitizeNames = fp.map(item => fp.flowRight(_underscore, fp.toLower)(item));


// 验证
let testAry = ['Hello World', 'Jonh Bob', 'ERD ARE DEE']
console.log(isLastInStock(cars), getNameOfFirstCar(cars), averageDollarValue(cars), sanitizeNames(testAry));